Yarn threading device for textile machines



Dec. 2, I952 R. DEWAS YARN THREADING DEVICE FOR TEXTILE MACHINES Original Filed June 5,

INVENTOR 1 Raymond Dewas B3 ()LQL... 1*

v ATTDYLEHS Patented Dec. 2, 1952 UNITED STATES PATENT OFFICE YARN THREADING DEVICE FOR TEXTILE MACHINES Raymond Dewas, Amiens, France March 16, 1946 6 Claims.

The invention relates to yarn tensioning devices which are used in particular in textile machines and which comprise two circular members called discs which are in contact with one another.

This case is a division of my co-pending patent application, Ser. No. 674,494, filed June 5, 1946, for Yarn Tensioning Devices, now Patent No. 2,457,450, dated December 28, 1948.

Objects of the invention are to improve the particular shape of the lower and upper discs, the arrangement of means for threading the yarn at the inlet of the tension device, which means are used, in particular, in the case of the yarn being unwound through a discontinuous, irregular or jerky take in, and also to improve various constructional details, as will become apparent from the ensuing description.

In order to make the invention more clearly understood, and by way of constructional examples which are in no way limitative, embodiments are described hereinafter and are diagrammatically illustrated in the accompanying drawings in which- Fig. 1 is a View in side elevation of a tension device having a plurality of aligned sets or pairs of discs, with a yarn threading device,

Fig. 2 being a plan View thereof.

Fig. 3 is a view in front elevation of the yarn threading device of which a side elevation is shown in Fig. 1 and a plan view in Fig. 2.

Fig. 4 is a view in front elevation of a similarly constructed double threading device for the case of two tension devices arranged side by side,

Fig. 5 being a plan view thereof.

In Fig. 1 are shown the component members of tension devices comprising discs provided with a central orifice, which rest on one another, in this case: a spindle l suspended by its headshaped end I on a fixed support 2, and also an upper disc 3 resting on a lower disc 4 which itself rests on a fixed ring 5 mounted at the end of the arm 6 of a support 1. The component members are, however, characterized, according to the invention, on the one hand by the fact that the spindle I, which no longer has to act but as a centering and retaining means of the upper disc 3 alone, ends above the level of the plane of contact of said disc with the lower disc 4, which plane coincides with that in which the yarn 11 passes, and on the other hand by the fact that the discs 3 and 4 are of such cross-sectional shape that the face of one of the discs, preferably the lower disc 4, which is intended to be in contact with the opposite disc, forms an annular fiat portion 4', whereas the opposite disc, preferably the upper disc 3, forms, on its contacting fact, an annular projection 3 which is adapted to rest against the fiat annular surface 4, the run of the yarn a as it passes between these two annular surfaces imparting to the discs a rotary movement which contributes to the evacuation of the material detached from the yarn, through the central evacuation orifice 4", and said evacuation may be assisted by a sweeping action which may be efiected by the yarn owing to the fact that, since it is no longer stopped by the lower part of the spindle I, it can, then, move transversely.

An improvement according to the invention consists in the fact that, for the threading, a vertical plate I9 is provided which is used in combination with a second plate 20 arranged parallel with and spaced a short distance apart from same, in order to form a yarn threading device by means of which threading by hand is readily and quickly effected.

The rear plate [9 which, in the example shown, supports the upper cross member 2 and the lateral cross member 1 which are fixed by means of screws 2' and 1, comprises a steel plate which is out out as shown in Fig. 3 and which has the appearance of a square of which the upper lefthand corner is cut off and amply rounded at 21 so as to form a guide edge for the yarn up to the opposite upper corner, after which the metal plate is recessed at 22 to form a threading nose 23 around which the yarn passes, and by following the upper inclined edge 24 of the recess, said yarn is thus guided towards the center of the plate to the end 25 of a slit 25 communicating with the recess 22.

The front plate 20, which is out of sheet metal, has the appearance of a rectangle of which the left-hand side has a large recess 26 for the inlet of the yarn fed from the bobbin as it unwinds, and the upper edge 21 of which is rounded in order to guide the said yarn to the end of said recess 26 which terminates in the shape of a slit 28. Said plate 20 is of suiiicient size for there to be no danger of the yarn catching as it un- Winds from the bobbin (not shown).

These two plates are arranged parallel with one another and are secured together by means of a small intermediate plate 29 and the whole arrangement is assembled by means of screws 30, the thickness of said plate 29 determining the gap between the two plates [9 and 20, between which the yarn passes during the manual threading operation.

This operation is efiected easily and, so to speak, instantly, by engaging the yarn in the recess 26 of the plate 20, then under the nose 23 of the plate 19, the insertion into the recess 22 being facilitated by slightly bending the nose 23, as shown at 23, along a crease 23". The positions of the plates I9 and 2E! and their components are adjustable, enabling the ends of the slits 25 and 28 to be juxtaposed, thereby forming a round or oblong threading eye for forming a bend in the yarn.

The yarn passing between the two plates, as shown at a in Fig. 2, is threaded between the two ends of the slits 25 and 28, the position of which is equivalent to the formation of an eye (as shown in Fig. 3). The yarn, after having then been inserted between the discs of the various sets of the tension device, is passed through a U-shaped guide 3| which is placed obliquely as shown in Fig. 2 and which closely holds the yarn a in its straight position while not preventing the thicker portions from passing, its being possible to turn the guide to enable the yarn to be shifted sideways the desired amount between the pairs of discs, in which case, and in order to allow of a corresponding transverse movement of the yarn as soon as it enters the tension device, the adjustment of the respective position of the threading plates I9 and may be effected in such a manner that the ends of the slits and 28 form the equivalent of an elongated eye.

In the case, for instance, of yarns having a high amount of twist, and if space is not available to enable a suificient number of sets of discs to be used, it may be advisable to form a bend at the inlet of the yarn into the tension device, so

as to contribute to the unkinking of said yarn.

Such a bend is obtained by adjusting the respective position of the threading plates [9 and 20 in such a manner that the ends of the slits 25 and 28 give the portion of yarn passing from one plate to the other the bend a" shown in dotted lines in Fig. 2.

When two tension devices are mounted side by side, the rear plate may be shaped similarly to the plate I9, so as to form, in combination with a front plate similarly shaped to the plate 20, a double threading device.

For this purpose, and as shown in Figs. 4 and 5, the threading plate Illa is so shaped as to have, symmetrically arranged, two noses 23a and two slits 25a, whereas the large threading plate Zila is provided with a single medial vertical slit which replaces the recess 26 and the edges of which, towards the center of the plate, taper outwardly on each side and form rounded edges 22a which guide the yarns respectively to the left and to the right in the end of the slits 28a, and said ends, by being superposed on those of the slits 25a, form the respective eyes of the two tension devices mounted side by side.

One of the plates lea or 20a may be vertically separated in two through the middle thereof so as to enable, by shifting its parts, either the equivalent of elongated eyes to be formed, or the portions of the yarn passing from one plate to the other to be given the bent position as hereinbefore explained.

Parts which are equivalent to those of Figs. 1 to 4 are designated by the same numerals.

It is also possible to obtain a double threading device by completing the single threading device of Fig. 3 by its equivalent arranged symmetrically with respect to the edge of the plate 2 0 opposite the recess 25.

It should be observed that the improvements relating to the absence of a spindle at the level of the plane of contact of the discs, to the shape of the discs and to the device having multiple sets of discs, may also be applied to tension devices in which the loading rings are replaced by springs, or act through the intermediary of springs.

On the other hand, and when the spindle ends above the level of the plane of contact of the discs, the upper disc need not have a central orifice and may in that case be centered on the spindle, for instance by means of a bush or a projection loosely engaged on or in a corresponding part of the spindle.

In the case in which two or more tension devices are mounted side by side, the upper cross members 2 may be connected together and optionally to the side cross members 7, or to the common side cross member 1, in any appropriate manner, and in particular by the underneath, externally, and similarly the assembly may be supported, also in any appropriate manner, by the threading plates or other members.

Finally, as regards the stop fingers ll, these may be fixed by their base on a lower member.

What is claimed is:

1. A yarn threading device for textile machines, comprising at least two separate, closely spaced, parallel, fiat plates of different sizes and shapes, a third intermediate flat plate of still different shape and size to hold the two first-mentioned plates on any one of its faces, and means adjustably securing said two-first-mentioned plates to said intermediate plate, whereby the thickness of said intermediate plate determines the gap for the yarn to pass between the two first-mentioned plates, one of the two first-mentioned plates being smaller in size than the other of the two first-mentioned plates and constituting the rear plate, said rear plate being substantially rectangular in form and having a rounded upper corner and a guiding nose constituting the second upper corner and located opposite the firstmentioned upper corner, said rear plate having formed therein a recess extending inwardly below said nose toward the middle of said rear plate and a slit communicating with said recess and having a rounded bottom located substantially in the middle of said rear plate, said recess having an inclined upper edge extending between said slit and said nose; the other one of the firstmentioned plates constituting the front plate and having formed therein a recess extending inwardly from a side of the plate in a direction substantially opposite that of the rear-plate recess toward the middle of the front plate and a slit communicating with the front-plate recess and having a rounded bottom located substantially in the middle of the front plate and adapted to be located adjacent to the bottom of the rear plate slit, whereby said two slits form a threading eye and whereby the shape of said threading eye may be varied by varying the relative positions of the front and rear plates, the front-plate recess having a rounded upper edge extending to the front-plate slit in a plane intersecting the rounded upper corner of the rear plate.

2. A yarn threading device according to claim 1, wherein the second one of the two first-mentioned plates is shaped to form, in symmetrical relation, two noses and two slits, whereas the first one of the two first-mentioned plates has both its upper corners cut oh and amply rounded so as to form guides for guiding yarns up to a single, medial slit, said slit having towards the center of the plate outwardly tapering edges forming rounded recesses for guiding yarns until they reach the ends of slits prolonging said recesses, said ends being superposed on the ends of the slits of the rear plate, and being in register, thereby forming threading eyes allowing two yarns to be threaded.

3. A yarn threading device according to claim 1, wherein two first-mentioned plates are adjustable relatively to each other, thereby enabling the registered ends of the slits to form threading eyes, or a bend in the yarn.

4. A yarn threading device according to claim 3, wherein the intermediate plate has a slide and bolts securing both the two first-mentioned plates to said intermediate plate, said bolts and said slide allowing the adjustment of the relative positions of the two first-mentioned plates.

5. A yarn threading device according to claim 1, wherein the noses of the rear plate are bent slightly outwards, thereby facilitating the threading of the yarns.

6. A yarn threading device according to claim 1, wherein a double threading device is formed by placing side by side two symmetrically constructed single threading devices.

RAYMOND DEWAS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date I 1,453,941 Madden May 1, 1923 1,543,139 Whipple June 23, 1925 1,672,471 Peterson June 5, 1928 2,202,937 Wolfe Jan. 24, 1938 FOREIGN PATENTS Number Country Date 478,656 Great Britain Jan. 24, 1938 

